Self-sealing ring-joint gasket



F. W. GOETZE SELF-SEALING RINGJOIN1 GASKET 7 3 Sheets-Sheet 1 June 10, 1947.

filed Nov. 5, 1945' llwelvrm firearm o. m gar/rm Wax-726, m R916 Cm Arr-M the grooves.

tofore manufactured, further require that the 'joint gasket engaging Patented June 10, 1947 Township, Somerset Co executrix, Franklin N. 1., assignor, Johns-Manville I Goetze, set County, ments, to

unty, N. 1.,

by Marie 0. Township, Somerby mesne assign- Corporation, New

York, N. Y., a corporation of New York Application November 5, 1945, Serial No; 626,640

' 6 Claims. (Cl. 288-24) This invention relates generally to gasket devices used for sealing joints formed in pressure piping or pressure vessels and relates more particularly to such gasket devices adapted to seal Joints which confine fluids under extremely hig temperatures and/or pressures.

More specifically this invention relates to gasket devices in the class commonly known as ringjolnt gasketsor wedge-ring gaskets which devices include relatively rigid metal rings as elements and in which the sealing eifect is produced by a wedging action of the rings into suitably shaped opposed grooves formed in the faces of the flanges with which the rings cooperate.

Ring-joint or wedge-ring gaskets, as generally,

manufactured, consist of elliptical, oval or other torroidal conformation in cross section. These rings are wedged, by means of bolts or other suitable clamping means, into a pair of opposed coaxial grooves formed in the joint flanges. The grooves are formed with converging sides and are accurately formed in the Joint flanges either by machining or by grinding. The metal of which these solid ringjoint gaskets are generally made is preferably relatively non-corrosive, and is usually rare and expensive.

These ring-joint or wedge-ring gaskets are used for sealing fluids confined under pressures of several thousand pounds and/or temperatures approaching 1000 R, such as are encountered, for instance, in hydraulic installations, high pressure superheated steam systems, oil refinery service, and the like.

When the service for which these solid gaskets are used is considered, it will be manifest that these ring-joint gaskets and the grooves in the flanges with whichthey cooperate must necessarily be carefully machined to extreme accuracy and close tolerances and must additionally be provided with a high quality of smooth surface finish in order that an intimate uninterrupted sealing contact may exist between the gaskets and These ring-joint gaskets, as heresolid rings of octagonal,

flanges or other Joint members formed with ringgrooves, be of'extremely heavy construction and that Very heavy bolts be provided, not only to force the solid ring-joint gasket into sealing engagement with the grooves but to maintain this sealing engagement under all ,variations in pressures and temperatures and under all variations in external stresses imposed on the joint structure. It will-also be evident that any slackening in the intensity of pressure e for creep of the bolts, gaskets between the flanges and the ring-Joint gasket or any slight lateral movement of the two opposed flange faces of the likely to cause leaks which, at the tremendously high pressures, are extremely serious.

In practice, in a joint in which a solid metal ring type gasket is used, the bolts are drawn up to a stress considerably in excess of that required to seat the'gasket in a sealing relation. This excessive tightening, beyond that required to seat the gasket, is carried out, (1) to resist the force'tending to separate the flanges when the internal fluid pressure is applied to the joint, (2) to insure the existence of a balance of sealing pressure on the gasket to maintain a tight joint when the internal pressure is applied, (3) to allow and flanges resulting from a, tensioning of these parts under high temperature for long periods of time and (4) to insure maintenance of sufficient bolting eifect in the event. that relatively sudden changes in pressure or temperature cause contractions or expansions of the elements or in the event that external mechanical distortions, shocks or vibrations are imposed on the joint. In actual practice it is almost impossible to predict the amount of bolt stress required to insure a tight joint under the conditions outlined.

Furthermore it is not possible, in the great majority of installations, to accurately measure the actual stress imposed on the bolts in tightening and overstressing frequently results with the consequent distortion of or breaking of the flanges or bolts or other severe damage to the joint or gasket. l

' In order to avoid the severe requirements in respect to heavy-construction and exacting refinements pointed out with reference to present rin -joint or wedge-ring constructions, and in order to avoid the need for imposing excessive stresses on the joint parts, it is a prime object of this invention to produce a ring-joint gasket which serves the purpose of and satisfies the requirements of, a ring-joint seal and which does not require the massive construction of joint members and the imposition of extremely heavy clamping pressures to secure and maintain a tight seal under the most severe conditions of temperature and pressure and under the most extreme and sudden variations in these conditions.

It is a-further object of this invention to produce a ring-joint gasket construction inwhich neither the gasket nor the associated joint members need to be finished to as close tolerances Joint forming structure, are a used.

It is a further object of this invention to produce a ring-joint gasket of this type which is self-sealing and in which an increase in the pressure of the confined fluid will automatically increase the pressure on the seal forming surfaces, as the pressure of the sealed fluid increases.

It is a further object of this invention to produce a gasket of this character which will permit a limited amount of axial separation and relative lateral shifting, in service, of the two juxtaposed joint flanges and grooves engaging the gasket, without danger of developing leaks.

'. It is a further object of this invention to produce a gasket of this character of which the parts can readily and rapidly be formed with dies by means of power press operations, thereby eliminating tedious and time consuming machining operations, and avoiding the need for compli-' cated and expensive finishing machinery.

It is a further object of this invention to .produce a ring-joint gasket which provides for ample accommodating movement or wiping action between the gasket and joint flange elements during the wedgi-ng and seating action which and partly insection 4 are sealed by one form .of the improved bellows type of rlng joint gasket embodying this invention, the gasket being shown partly in elevation on a median plane thru the gasket, the plane of the section being indicated by line I, I in Figure 2.

takes place when the flanges are drawn into sealing engagement with the gasket.

It is a further object of this invention to produce a ring-joint gasket which is more economical in the use of expensive metals than solid ring-joint gaskets of the type generally used at present.

It is a further object of this invention to produce a ring-joint gasket having the advantages pointed out and in which certain essential comonent parts of the gasket serve as a centering guide adapted to accurately position the'gasket during installation with reference to the ealing surfaces in the flanges.

These and other objects may be obtained by the elements, parts, combinations and constructions constituting the present invention, preferred and modified embodiments of which are shown in the accompanying drawings and are hereinafter described in detail and claimed, which may be stated in general terms to include in a gasket construction, an annular bellows type of sheath hermetically sealed at its outer periphery and spaced apart interiorly thereof and formed adjacent its inner periphery with a pair of axially opposedinteri'or alined annular grooves and corresponding exterior convex annular surfaces, and a pair of similar annular inserts normally contacting each other approximately on the median plane of the gasket, each insert being seated in one of the grooves in the sheath, the two inserts forming the equivalent of the ringjoint type of gasket in respect to its relative incompressibility and the bellows type of sheath forming a means for maintaining the inserts in proximate alinedrelation and also serving by confining the fluid pressure to force the inserts and convex surfaces of the sheath into increasingly tighter fluid sealing engagement with the grooves formed in the faces of the flanges associated with the gasket,-as the pressure of the sealed fluid increases.

Referring to the drawings: Fig. 1 is a fragmentary transverse section of a joint formed between adjacent ends of two alined pipes forming a conduit, the pipe ends being provided with companion flanges which Fig. 2 is a fragmentary axial section of the joint shown-in Fig. 1, this section being taken on the plane indicated by line 2, 2 in Fig. 1, the bellows type of ring-joint gasket sealing this joint being shown in a closed position, that is a position showing the relation of the parts at the conclusion of the assembling of the joint elements after the bolts have been drawn up to the required degree of imposition of any internal fluid pressure or loads on the joint of sufllcient intensity to cause any relative change of position of any of the gasket or joint elements.

Fig. 3 is an enlarged view of the bellows type of ring-joint gasket illustrated in Fig. 2 and detached from the associated joint structure shown inFig.2.

Fig. 4' is a view of the parts illustrated in Fig. 2,thebellows type of ring-joint gasket being shown in a slightly open or axially expanded position (necessarily somewhat exaggerated), this position representing the effects on the joint parts caused by certain variations inpressure and/or temperature to which the joint is subjected, as will be hereinafter pointed out.

Fig. 5 is an enlarged view of the gasket. as illustrated in Fig. 4, detached from the associated the axis of the passage thru the gasket.

joint structure.

piece of sheet metal, that is without a hermetically sealed connection at the outer periphery such as shown in disclosuresin the preceding figures, and in which the opposed faces of the horizontally extending portions of the sheath are substantially in contact with each other along a median plane of the gasket, in the normal or free position of the gasket.

Fig. 7 is a view of a gasket similar to that shown in Fig. 6 also showing the sheath made on one integral piece of sheet metal but with the opposed faces of the horizontally extending portions of the sheath slightly spaced apart, and also showing an arrangement of certain radial grooves in the inserts or cores slightly different from that shown in Figures 1 to 6.

Fig. 8 is an inside edge view of the gasket shown in Fig. '7, this view being taken from a point on the axis of the gasket.

Fig. 9 is a view of a gasket similar to that shown in Figure 2., illustrating a modified type of weld used for hermetically sealing the outer peripheral edges of is made on one integral sheath.

Fig. 10 is a view of the parts illustrated in Fig. 9 showing the position occupied by the parts when the gasket inserts or cores are spaced apart slightly as occurs under certain conditions in service.

Fig. 11 is a view of a gasket similar to that shown in Fig. 3, showing, however, the cores and sheath of octagonal cross sectional form.

In the following specification the term axial, when used with reference to parts of the gasket or associated joint elements, is intended to indicate a direction parallel to or in the direction of The term radial is intended to indicate a direction tightness and prior to the the sheath, and showing slight 1y modified inserts or cores enclosed in the rections away from 2,42aco9 .transverse to the axis of the passage thru the gasket, that is, in a direction radial with respect to the center of the gasket and Joint. The term median plane when used with reference to portions of the gasket is intended to indicate a plane plane of the gasket in an axial'direc'tion.

Referring first to the form of this invention illustrated in Figures 1 to 5, there are indicated fragmentarily at 1 and2 opposed alined pipe sections' having threaded connections with flanges i! and I, respectively, each formed with a plurality of registering bolt holes 5 and 6. As will appear, the pipe sections I and 2 form a substantially cylindrical passage or conduit 1 defined by the alined interior walls ofthe pipe sections l and 2. A plurality of suitable bolts 8 passing thru and loosely fitting in the holes 5 and 6 are adapted to advance the flanges toward each other, thus serving as ameans for forcing the joint members into the proper engagement with the elements of the interposed gasket unit hereinafter to be described.

The flanges 3 and 4 are each formed with opposed annular substantially parallel faces II and i2 respectively, pipe sections I and 2, and preferably interiorly of the bolts ll. Opposed annular coaxial grooves, indicated at I 3 and H are formed in the annular face portions ll flanges 3 and 4. These grooves may assume any one of various configurations in transverse cross section. In the form illustrated in Figures 2 and 4, these grooves are shown tapered in cross section with the side walls diverging toward the annular faces of the flanges in which they are formed.

The construction of the improved self-sealing ring-joint gasket will be best understood by reference to the plan view, Figure 1 and transverse sections, Figures 2 and 3. This gasket consists of an annular bellows or double diaphragm type of sheath,venclosing and conforming, in part, to' the axially outer contour of a pair of juxtaposed relatively hard annular inserts or cores.

The annular bellows type of sheath is preferpositioned next exteriorly of the I and I2, respectively, of the ably made of sheet metal and is indicated in its in the embodiment of a pair of preferor bellows elements entirety at l5 and is formed illustrated in Figures 1 to 3, ably identical annular sheath l6 and I1.

The sheath elements veniently produced in dies. Each sheath element is shaped, adjacent its radially inner periphery, into the conformation of an annular corrugation l8 forming an annular groove l9, interiorly of the sheath, and an annular'convex surface 20 exteriorly of the sheath. Extending radially outwardly from the corrugation l8 on each sheath is I 6 and I! are most con- I a substantially flat annular web or diaphragm section indicated at 2|. The sheath elements l6 and I1 are superposed one upon the otherin coaxial relation and secured together at their outer periphery with the grooves l9, iii of the elements facing each other, as clearly appears in Figures '2 and 3. The method of securing the two sheath elements together is optional and may be effected by seaming, brazing, welding or any other desired method which insures the formation of 0d of securing the sheath elements together is edges of the webs the median plane of the gasket where they are each formed with a generally flat surface 25. On the side away from the median plane, that is on their'axially outer faces, the cores 23-are each formed with a convex surface 24. The convex surfaces 24 are accurately produced preferably dies, to substantially the same conthe grooves I 9, in order that the cores may snugly seat or nest within the grooves I9, iii. In practice, the radial width dimension of the cores is preferably made slightly greater than the radial width of the grooves in the sheath in order that the cores may engage the grooves in the sheath with a tight friction fit.

The overall axial dimension of the groove l9 in the sheath element is nearly the same but preferably slightly less than the axial height of the cores, in each case, in order that the sheet metal which forms the corrugation on each sheath element may enclose the core almost completely. The edges 26, 26 forming the radially inner terminals of the. corrugations l8, l8 are accordingly spaced apart as shown in Figures 2 and 3, forming" an annular opening, indicated at 21, when the cores 23, 23 are in contact with each, other. The opening 21 serves to insure access of the fluid pressure in the conduit tothe inner walls of the cores 23, 23 particularly at the median plane in which the flat faces 25, 25 of the cores. contact each other. The radially outer walls of the corrugations l8, 18 cover the outer sides of the cores 23, 23 and flare into the diaphragm sections, in the embodiment illustrated in Figures 1 to 3.

passage 1 interiorly the faces 25, 25 are in contact with each other.

The inserts or cores 23, 23 may be formed in any desired manner as by machining, forging, stamping or by a. combination of these methods. They are, however, preferably formed from flat sheet metal in suitable dies by means of a power-pressby a series of successive blanking, forming, curling, and coining operations. The metal from which the cores are made is preferably of relatively inexpensive steel which is hardened bythe cold working operations to which the cores are subjected in the press operations.

The sheath elements l6 and I! are preferably made from relatively thin sheet metal in blanking and forming operations in suitable dies, both elements being made in the same dies. The sheath is preferably made of metal softer than the metal used for the cores. In some cases soft steel will be satisfactory, but in those caseswhere a corrosion resisting material is required, other metals such as stainless steel, phragm portions 2|, 2| of the sheath elements, monel metal, bronze, brass, etc., may be utilized. passing into this space thru the radial grooves In the producing of this improved ring-joint 29. It is here noted, however, that these grooves gasket unit the preferred sequence of steps used are not always essential as the pressure very is as follows: The sheath element or diaphragm easily seeps between the contacting faces 26 of sections 16 and I1 are each formed in blanking the cores to the space 28 unless the two conand forming dies. The inserts or cores 23, 23 are tacting faces 25 should temporarily adhere tomade in suitable blanking, forming, curling and gether in which case the opposed axially directed coining dies. A core 23 is then inserted and posipressures on the surfaces of the grooves 28 serves tioned in each of a pair of sheath elements, to force the'cores apart. The enclosed fluid preswhereupon the two sheath elements are assemsure, of course, also acts on the terminal edges bled with the cores facing each other and are 26 of the sheath at its inner periphery. The held in suitable fixtures adapted to substanpressure in the space 28 and the pressure extially aline and maintain the two sheath elements erted on the inner periphery of the terminal in coaxial relation and to hold the faces 25, 25 edges 26 and the pressure acting on the faces 25 of the cores and the outer peripheral edges of the of the cores all cooperate to force these gasket sheath elements respectively, in contact with each elements axially outward from the median plane other, in which 'position the two sheath elements of the gasket and to force the convex surfaces are welded together at their outer periphery. 20, into intimate engagement with the grooves The assembling of this ring-joint gasket in the 20 I3 and i i. joint to be sealed proceeds as follows: The flanges A position of the parts when the fluid pressure 3 and, d are first separated until the space beis exerting its full effect on the parts of the joint tween the opposed faces H and I2 of the flanges, is illustrated in Figures 4 and 5 where the cores between which the gasket is to be inserted, is 23, 23 and the inner p phe ies o th sheath greater than the overall thickness of the gasket elements l6 and H are shown forced apart as a in an axial direction. The gasket is then slid or result of the imposition of an extremely high dropped in between the flanges depending on pressure on the joint. In the absence of ea whether the axis of the conduit is vertical or horinit al strain in t e b s, th imposition of h zontal, two or more bolts 8 having preferably been pressure normally results in a slight elongation inserted in the bolt holes to serve as stops or 3 of the bolts 8 which permits the sli axial 0 guides against which the periphery of the gasket d movement f e gasket P ts om t will abut, thus insuring the proper positioning median plane of the gasket, the extent of the of the convex surfaces 20, 20 of the gasket co- I pen n bei g slightly a erated in Figu s 4 axially with the grooves l3 and M in the flanges. and 5, for purposes of clearness in the drawing, The gasket having been properly positioned beas will be nder tood.

tween the flanges, the remaining flange bolts 8 W en the imposition of this Pressure is are inserted in the bolt holes and are drawn up c mpanied by hi h temperature, or when variin successive around the joint until all bolts are ations in temperature still h r to strained equally to the predetermined extent, at ti s t e place in the gasket parts. in th which time the surfaces 25, 25 of the cores 23, 4o flanges, and in the bolts. 23 will be in close contact with each other and Further distortions in gasket or joint parts may the convex surfaces 24, 2% of the cores will be l o r ult from a lag in the transmission of snugly seated in the grooves l9, I9 and the comthe mp r r f m he inte ior of he cond t vex surfaces 20,20 of the sheath will be in presto e outer joint parts. u h a lag may cur.

sure sealing engagement with the axially o t, for example, in the event that a sudden drop wardly converging side walls of the grooves l3 in temperature takes place in the conduit causand M. For reasons which will be hereinafter i g the gask t n fl s to ool and contract explained, it is not essential that the bolts be before the bolts have cooled suflioiontly to drawn up with any exceedingly heavy initial tract n the same proportion as the as et and strain, as a strain insuring a continuous intimate flanges, and Figure 4 y be assumed to i contact around the entire periphery between the irate the relative position of the P r s der groove walls and the outer convex surfaces of these circumstancesthe sheath is sufficient, a will b e d, Likewise external mechanical longitudinal or Pursuant to the assembling procedure just detransverse stresses may be po on he onscribed, and prior to the imposition of internal duit iint Pertsi which n to distort the Joint re r emperature upon the joint, the ga parts; but regardless of the distortion which ket and joint arts assume the position illustrated kes place, the internal pr ssure within the in Figures 2 and 3. gasket maintains the convex surfaces 20, 20 of When a. oderate inter al pressure is d v lthe sheath element in intimate fluid sealing enoped in the conduit 1, the pressure sealing enement with the grooves i3 and I4 and it has gagement of the convex surfaces 20, 20 of the been found that this self sealing bellows type sheath with the walls of the grooves l3 and I4 f ing-joint gasket construction i especially is amply sufllcient to prevent leakage. Any subadvantageous in installations subject to shock or stantial increase in internal pressure developed ibrat on.

within the passage 1 instantaneously exerts a Due to the relativ softness of the metal of pressure :on the axially inner faces 25 of the the sheath compared with the metal of the flanges cores 23, thus forcing the cores outwardly in an d w th the et l of the core t wi be c e r axial direction in proportion to the intensity of that the sheath at its po n f engagement w t the pressure. This axially outward pressure is the groov s dily conforms to the general contransmitted by the cores. against the corrugation tour of the grooves and to the local surface irin the sheath and causes the convex surfaces 20, regularities of the grooves and cores, even to 20 of the sheath elements 16 and I! to more inthe extent of deforming slightly in producing an timately seat in the grooves l3 and I4. effective pressure sealing engagement with the The pressure originating in the passage 1 also grooves in the flanges. Under some circumpasses into the open space 28 between the diastances, in fact, tool marks on the cores or in the grooves are an advantage they tend to improve the sealing bond or binding between the metal of the sheath and the relatively harder metal of the cores and flange grooves.

It will also be clear that, due to the capacity of the sheath to conform to minor irregularities in the flange grooves and core surfaces, the need for precision accuracy in the finish of flange grooves or joint elements is avoided, as a result of which the parts may be produced more rapidly and with more simple machinery.

During the bolting up action it will be clear being interposed between the from the groove in the out any su stantial unbalanced or eccentric load on the cores.

It will be apparent that the intensity of the pressure sealing engagement between the convex surfaces 20, 20 of the sheath and the walls l3 and i4 produced by the pressure of the sealed fluid, will increase with an increase in the pressure of the sealed fluid, that is it will automatically vary with the pressure of the sealed fluid and will be in proportion to the need for tightness of the sealing effect required. It will also be evident that this sealing efiect will obtain regardless of a limited axial separation or relative lateral shiftaction incident to the movements of gasket or portion of the cores.

As stated above, the cores are originally made "for a snug friction seat in the grooves of the 1o corrugations and the intimacy of the contact between the core and the sheath is increased as a result or the pressure and temperature conditions to which the assembling and in service. It is noted, however, that the original snug fit of the core in the not always essential as cores with relatively loose original fits insheaths were found to be tightly seated inthe sheath after assembling and short periods of service under the high pressure and temperature.

This self sealing or bellows type of ring-joint gasket may be modified in a number ofrways within the scope of this invention and a few of these modifications are shown in Figures 6 to 11.

Figure 6 illustrates a modified form of this invention in which the sheathis formed of a single piece vof sheet metal instead of two identical pieces welded together at the outer periphery, as in the hereinbefore described form of gasket. This sheath is illustrated in its entirety at 30 and comprises an up a lower sheath portion periphery of the diaphragm sections 31, 31 as shown at Seated sheath portions 3| and 32 and otherwise bear i the same relation to the corrugations as in the first above described form of this invention.

In the modification illustrated in Fig. 6, the

enclosed withno 'open space is provided between phragm sections 31, 31,

44, 44 integrally forming an outer periphery 45;

generally similar previously described cores and bearing the 11 same relation to the corrugations as in the previously described forms of this invention. The cores 41 and 48 differ, however, from the previously described cores in respect to the abutting faces on the median plane of'the cores. The lower face of the core 41 is formed with a radial groove 49 while the upper face of the core la is formed with an uninterrupted smooth face. The radial groove in one of the cores has been found to be completely ample in many installations, to quickly transmit the fluid pressure between the cores and into the space 46.

The form of the invention illustrated in Figures 9 and 10 comprises a sheath 50 formed of two similar stampings and 52 each formed with a corrugation 53 and a radially outwardly extending webor diaphragm section 54, the diaphragm sections 54 being sealed together at their outer peripheries by means of an arc weld as shown at 55. Seated in the corrugations 53, 53 of the upper and lower sheath portions 5! and 52, are a pair of cores 56 and 51, respectively. These cores are generally similar in conformation and bear the same relation to the corrugations as in the previously described forms of this invention. These cores 53, 53 however, are formed of solid metal instead of sheet metal as in the case of the previously described cores. These solid cores are preferably made by a forging and/or machining operation and a final coining or sizing operation. The core 58 is preferably provided with a radial groove 58 on its lower face, pro- ,viding ready access of fluid pressure to the area between the cores and between the diaphragm v sections 54, 54.

The position of the parts of this gasket when subjected to high fluid pressure is clearly indicated at Fig. 10.

Fig. 11 shows a gasket embodying this invention in which the portions adapted to cooperate with the grooves in the flanges are, as a whole, octagonal in transverse section. This form of the invention includes a sheath 60 comprising upper and lower sheath portions SI, 62, each formed with an annular trough like corrugation 63, having a flat axially outer surface 64 and axially outwardly converging side portions 65, 65, the outer surfaces of these convergin sides being adapted to form sealing engagement with the walls of correspondingly converging grooves in flanges, not shown, but generally similar to the flanges illustrated in Figures 1 to 5. Extending radially outwardly from the corrugations 63, 63 are diaphragm sections 66, 66 hermetically connected together at the outer periphery by a resistance weld 61. The diaphragm sections 66, 66 are slightly spaced apart to form an intervening space 68. Seated within the groove 63, 63 are a pair of cores 65, 69 of the same general conformation in transverse section as the corrugations 63, 63 in which they snugly nest. The cores 69, 69 as illustrated, are made by a series of blanking, forming, curling and coining operations in suitable dies.

In all of the above disclosures, the sheaths and cores have been shown and described as annular in form. It will be clear however, that this invention in its broader aspects, is not limited to an annular or circular gasket but may be embodied in any other closed form such as elliptical, oval or any other endless conformation and .it is intended that the term annular as used in the claims may be accordingly interpreted broadly. Many other modifications of this invention and its application in addition to those Shown, will naturally occur to those skilled in this art, and the present disclosures should therefor be considered as typical only, and applicant desires not to be limited to the exact construction shown and described.

In the foregoing description have been utilized for brevity, clearness and understanding; but no unnecessary limitations should' be implied therefrom because such words are utilized for descriptive purposes herein and not for the purpose of limitation, and are intended to be broadly construed.

What is claimed is as follows:

l. A gasket construction of the character described, comprising a pair of ring-like core members disposed in face to face relation with their openings axially alined and with their axially outer surfaces having convex shape, and a bellows type of sheathing enclosing said core members, said sheathing having a pair of walls formed with openings axially alined with the openings in said core members, and each wall having an inner marginal portion disposed axially exteriorly about the convex surface of one of said core members and having a portion extending radially outwardly from said opening and terminating in an outer margin, said outer margins of the two walls being hermetically connected together.

2. A gasket construction of the character described, comprising a pair of axially juxtaposed ring-like core members each having an axially outer surface of convex shape, and a bellows type sheathing enclosing said core members and having walls defining openings in axial alinement with the openings of said core members, said walls being hermetically connected along portions radially remote from said openings and having radially inner portions free to move adjacent to said openings, the movable portion of each of said walls having a radially outwardly also, certain terms convex inwardly opening corrugation enclosing one of said core members.

3. A gasket comprising in combination an annular sheet metal sheath and a pair of solid annular cores substantially enclosed within the sheath, the cores being of the same diameter and each being formed on its axially inner face with a flat surface substantially square with the axis of. the cores and on its axially outer face with a convex surface, the sheath being formed with a pair of walls having substantially central opposed coaxial grooves of substantially the same conformation as the convex surfaces of the cores and being provided with an annular substantially central opening in each wall and with a hermetically closed connection between the outer peripheries of the walls.

4. A gasket construction of the character described, comprising a pair of annularly-shaped core members, solid in cross-section, and normally substantially engaging each other in face to face relation substantially on a median plane thru the gasket, with their openings axially alined and with their axially outer surfaces having convex shape, and a pair of sheathing walls, her- -metically connected together radially exteriorly of the core members, and having radially inner portions formed with axially outwardly extending grooves frictionally embracing the core members.

5. A gasket construction tween adjacent ends of axially alined conduit members of a pressure line, comprising a pair of walls having axially disposed apertures axially adapted for use he- 13 alined to permit communication between said conduit members, the outer marginal portions of said walls being hermetically connected, and the inner marginal portions of said walls being free to move with iespect to each other in axial directions, the inner marginal portion of each wall having formed therein an outwardlyconvexinwardly opening seat surrounding the aperture in said wall, and a pair of separate coremeans of material harder than the walls of said gasket each having an axially outer surface conforming to one ofsaid seats frictionally held therein and movable therewith.

6. A gasket comprising in combination an annular relatively soft sheet metal sheath and a pair of relatively hard juxtaposed annular cores enclosed within said sheath, said sheath comprising a pair of substantially parallel spaced wall portions hermetically connected together adjacent their outer-peripheries and formed on their interior surfaces adjacent their inner peripheries with axially opposed annular grooves extending in opposite directions from the median plane of the sheath, the pair of core each having its axially outer face of convex conformation in transverse section and seated in one of said 14 grooves, the axially inner faces of said cores being adapted to engage each other, and means in at least one of said cores providing a radial passage when the said inner faces of said cores are .in engagement with each other. a

, MARGlEC. GOETZE, Executria: of the Estate of Frederick W.

Goetze, Deceased.

file of this patent:

UNITED STATES PATENTS Number Name Date 1,904,250 Purvis Apr. 18, 1933 836,950 Wilcox Nov. 2'7, 1906' 2,291,709 Goetze Aug. 4, 1942 2,401,923 Gleeson June 11, 1946 2,384,672 Gleeson Sept. 11, 1945 1,715,854 McKenzie et al June 4, 1929 FOREIGN PATENTS Number Country Date 614,140 Germany June 3, 1935 

